The use of multi-wire electrical cables has increased over the last few years, and this has, of course, increased the need for assuring that all of the wires included in such a cable are in good operating condition. When one or more wires included in the cable become open, as can occur, for example, by the wire being broken somewhere between the opposite ends, this reduces the overall effectiveness of the cable and, in at least some cases, makes the cable unsatisfactory for its intended use.
It has therefore been quite important, at least for some uses, that all of the wires included in the cable be reliable in transmitting electrical signals through each of the wires included in the cable. This is particularly important for a multi-wire cable that is to be used as a seismic cable. Therefore, it is desirable that such a cable be tested during final check-outs in field operations to assure reliability.
While various devices and/or methods for checking multi-wire cables have been heretofore suggested and/or utilized, none has been fully satisfactory in providing a relatively simple, portable unit and a method that can be utilized to rapidly check all of the wires of a cable and reliably indicate wires in the cable that are open.
Multi-conductor cable testing apparatus and methods are known in the prior art, and such apparatus is shown, for example, in U.S. Pat. Nos. 4,134,099; 4,074,187; 4,052,694; 4,015,200; 3,986,106; 3,944,914; 3,665,299; and 3,594,635.